Differential pressure sensors are used to measure a difference between pressures of two fluid environments. These two fluid environments may be located nearby one another or at great distance one from another. Differential pressure sensors come in at least two varieties: i) true differential pressure sensors; and ii) pseudo differential pressure sensors. True differential pressure sensors provide fluid communication between each of the two environments and to each of two sides of a differential pressure transducer, respectively.
Pseudo differential pressure sensing can be accomplished using two distinct absolute pressure sensors. Each absolute pressure sensor is exposed to one of the two fluid environments so as to measure that fluid environment's absolute pressure. By taking the difference of resulting signals indicative of absolute pressures of the two fluid environments, a signal indicative of a difference between the two absolute pressures can be generated.
Various types of pressure sensors have various advantages and disadvantages. In some circumstances, for example, it may be undesirable to expose both sides of a differential pressure sensor to high pressures. In such cases, a pseudo differential pressure sensor may be preferable to a true differential pressure sensor. In some cases, the two fluid environments may be located at a great distance one from another. In such cases, use of two remote absolute pressure sensors may provide a good solution for measuring a pressure differential.
Failure of a differential pressure sensor can be problematic in some applications. If, for example, one of the two bridges of a differential sensor has a sensor failure, then the differential pressure sensor is rendered incapable of measurement of differential pressure. Failure to measure a differential pressure can cause a system to perform poorly or to cease performance altogether. Suboptimal performance can waste money and/or present a danger to people. For some such systems where these deleterious consequences can arise, improved sensor reliability can provide increased safety and/or prevent wasted expenses.